Intrusion detection fence with trip wires and common actuator

ABSTRACT

An intrusion detection fence and system is provided. In one embodiment, the fence includes a plurality of trip wires secured between a pair of anchor posts, a plurality of detector posts anchored in the ground, located between the anchor posts, at least one actuator attached to each of the detector posts, the actuator also being coupled to each of the plurality of trip wires; and a detecting device attached to the actuator and secured to each of the detector posts. The deflection or cutting of any of the plurality of trip wires activates at least one of the detecting devices adjacent to the activated trip wires.

FIELD OF THE INVENTION

The present invention relates to intrusion detection system in general,and specifically to fencing systems utilizing taut wires and detectordevices to detect intrusion.

BACKGROUND OF THE INVENTION

Numerous types of intrusion detection fences have been developed inorder to successfully detect attempts of intruders to circumvent thesystem. Reference is now made to FIG. 1 which illustrate a typical priorart system such as U.S. Pat. No. 4,367,459 to Amir which consists of afence having a plurality of trip wires 12 secured between two anchoredposts 14 and a detector post 16 located between the anchored posts 14. Adetecting device 18 such as a transducer is fixed to the intermediatedetector post 16. Typically, the anchor posts 14 are located between 30and 60 meters apart, that is the detector post 16 is approximately 15-30meters away from an anchor post 14. The plurality of trip wires 12 areconnected to a common actuator 20, which is supported by detector post16. Any change in the lateral tension of wire 12 due to bending orcutting of the wire, for example, is ‘received’ by the common actuator20 and transmitted to the transducer (detecting device 18).

The larger the distance between detector post 16 and anchor posts 14,the less sensitive the detection system. This is especially so in thevicinity of the anchor posts 14 further away from a common actuator 20,since as a result of the lateral movement of the wire deflectionadjacent to the anchor post 14 is at a minimum near the common actuator.

In order to overcome these disadvantages, wire guiding posts 22 areplaced between the detector posts 16 and between the anchor post 14 andthe detector posts 16 to guide the wires 12 which slide through themwithout being held by them (the wires are not secured to the guidingpost 22).

In a further variation as illustrated in FIG. 2, it is known to use oneor more helical wire supports 24 between the common actuators 20 (inplace of or in addition to wire guiding poles of FIG. 1). These helicalwire supports 24 also act as sliding supports which translate thevertical motion of the wires, which have been bent or cut, into alateral movement which can be sensed by the common actuator 20 anddetected by the detecting device 18 connected to the common actuator 20.

However, these helical wire supports 24 (as shown in FIG. 2) or wireguiding posts 22 (as shown in FIG. 1) have the disadvantage that theycan be easily mechanically cut, broken or removed by the intruder,actions which may not trigger the alarm. Thus, if an intruder has enoughtime, the removing or cutting of the helical wire cases the fence tolose its sensitivity. Thereafter, the intruder can, in some situations,move the taut wires apart without triggering the detecting device 18.

U.S. Pat. No. 4,829,287 to Kerr, schematically illustrated in FIG. 3 towhich reference is now made, utilizes a plurality of detector posts 30between anchor posts (not shown) and a plurality of sensors 32 which aremounted on each detector post 30. Each of the parallel taut wires 34,anchored to the anchor posts, engage a single sensor. Betweenhorizontally consecutive sensors, wire guiding devices comprising a rodand helical coil support members 36 (similar to FIG. 2) are placed toguide the taut wires 34, keep them apart and translate the bendingmovement of the wire into a lateral motion through the helical coilsupports.

Intrusion detection systems having a sensor fitted to each taut wire aremuch more expensive, since they require a sensor for each strand ofwire, and consequently also require a great deal more maintenance.Eventually, the sensor parts of the taut wire system which arerelatively costly and the most vulnerable parts of the system lose theirsensitivity especially if not properly maintained. Therefore, these“sensor for each wire” type systems are much more expensive incomparison to the “common actuator” type of fences mentioned above.

While the “common actuator” type fences are less expensive are generallyless sensitive especially when the intruder removes or breaks thehelical or guiding posts and thereby reducing the fence's sensitivityand causing the fence to deteriorate and become less effective.

SUMMARY OF THE PRESENT INVENTION

It is an object of the present invention to provide an improvedintrusion detection fence utilizing a plurality of tensioned taut wires,which overcomes the limitations and disadvantages of prior art systems.

It is a further object of the present invention to improve thesensitivity of the system by reducing the opportunity for intrusion evenwhen the intruder tries to reduce its sensitivity by removing or brakingone or more of the guiding posts or helical supports. In the preferredembodiment, the intrusion detection system includes a plurality ofactive sensor devices each connected to a common actuator. The activesensor devices are placed between anchor posts which tautly restrain thetaut wires.

There is therefore provided, in accordance with a preferred embodimentof the present invention, an intrusion detection fence, which includes aplurality of trip wires secured between a pair of anchor posts, aplurality of detector posts anchored in the ground, located between theanchor posts, at least one actuator attached to each of the detectorposts, the actuator also being coupled to each of the plurality of tripwires; and a detecting device attached to the actuator and secured toeach of the detector posts. The deflection or cutting of any of theplurality of trip wires activates at least one of the detecting devicesadjacent to the activated trip wires.

Furthermore, in accordance with a preferred embodiment of the presentinvention, deflection of any of the plurality of trip wires activateseach of the detecting devices either side of the activated trip wires.

Furthermore, in accordance with a preferred embodiment of the presentinvention, the actuator is an actuating wire tensioned between the endsof the detector post. The actuator is an actuator bar or flange.

Additionally, in accordance with a preferred embodiment of the presentinvention, the fence further includes a passive wire attached to each ofthe detecting device, the passive wire being parallel to the actuatorwire.

In addition, in accordance with a preferred embodiment of the presentinvention, The detecting device is housed within a central leg of agenerally “I” shaped housing, the housing further includes a bottom legand a top leg attached to the central leg. The housing further includesa pair of clamps attached to the top leg for clamping common actuatorwire and passive wire to the detecting device.

In addition there is also provided, in accordance with a preferredembodiment of the present invention, an intrusion detection system whichincludes a fence having a plurality of trip wires secured between a pairof anchor posts, a plurality of detector posts anchored in the ground,located between the anchor posts, at least one actuator attached to eachof the detector posts, the actuator also being coupled to each of theplurality of trip wires, a detecting device attached to the at least oneactuator and secured to each of the detector posts: and a control centercoupled to each of the detecting devices. The control center includes aprocessor for determining and indicating the location of detectingdevice activated by the deflection of any of the trip wires.

In a second embodiment, in accordance with a preferred embodiment of thepresent invention, the system and fence further include a plurality ofguiding posts, each guiding post being located between each pair ofdetecting posts or between a anchor post and a detecting post. Theactuating wire is tensioned between the top of one of the guiding postsand the bottom of the adjacent guiding post. Alternatively, theactuating wire is tensioned between one end of one of the guiding postsand the end of one of the anchor posts.

Furthermore, in accordance with a preferred embodiment of the presentinvention, the fence and system further include a second detectingdevice attached to at least one of the pair of anchor posts.

Furthermore, in accordance with a preferred embodiment of the presentinvention, the actuating wire is further tensioned between the top andbottom ends of one of said pair of anchor posts and attached to thesecond detecting device. Alternatively, the actuating wire is furthertensioned between the top or bottom end of an anchor post and attachedto the second detecting device.

Furthermore, in accordance with a preferred embodiment of the presentinvention, the fence and system further includes a second actuating wireattached to and tensioned between the top and bottom ends of the anchorpost and attached to the second detecting device.

Additionally, in accordance with a preferred embodiment of the presentinvention, the fence and system further includes second and thirdactuating wires. The second actuating wire is tensioned between one endof one of the pair of anchor posts and the third actuating wire istensioned between the other end of the anchor post.

Furthermore, in accordance with a preferred embodiment of the presentinvention, the detecting devices are torque sensitive devices.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will be understood and appreciated more fully fromthe following detailed description taken in conjunction with thedrawings in which:

FIG. 1 is a isometric illustration of a prior art common actuatordetection system;

FIG. 2 is a isometric illustration of a further prior art commonactuator detection system using helical wire guides as guiding posts;

FIG. 3 is a isometric illustration of a further prior art detectionsystem using a plurality of sensors on each detector post;

FIG. 4 is a isometric illustration of a detection system, constructedand operative in accordance with an embodiment of the present invention;

FIG. 5 is an isometric illustration of a preferred embodiment of adetector post of the detection system of FIG. 4;

FIG. 6 is an enlarged detail illustrating the connection of the actuatorwire to the detector post of FIG. 5;

FIG. 7 is a schematic illustration of a detection system, constructedand operative in accordance with a further embodiment of the presentinvention;

FIG. 8 is an enlarged detail of the detection system of FIG. 7;

FIG. 9 is an isometric illustration of an anchor post of the detectionsystem of FIG. 7; and

FIG. 10 is an enlarged detail illustrating the connection of theactuator wire to the detector post of the detection system of FIG. 7.

DESCRIPTION OF THE INVENTION

Reference is now made to FIG. 4 which is an isometric illustration of ataut wire detection system, generally indicated 50, constructed andoperative in accordance with an embodiment of the present invention.

Detection system 50 consists of a fence having a plurality of trip wires52 tautly secured between anchor posts 54. A plurality of detector posts56, which are fixed to the ground to prevent movement, are locatedbetween anchor posts 54.

Each detector post 56 supports at least one common actuator wire 60which is attached to each of the taut trip wires 52 by any suitablemeans, such as clips (not shown) which are suitably fitted around thetrip wires 52. It will be appreciated by persons skilled in the art thatthe common actuator devices are not limited to actuator wires but alsoother mechanical assemblies could be applied such as bars and flanges asdescribed in U.S. Pat. No. 4,367,459 to Amir, for example. A detectingdevice 58 is suitably connected to each common actuator wire 60. For thepurposes of illustration only, detecting device 58 is locatedapproximately mid-way along each common actuator wire 60. Each of thedetecting devices 58 is coupled to a control center 66.

The common actuator wire 60 is suitably attached to each end ofdetecting post 56 such as by use of restraining brackets 62. Preferably,common actuator wire 60 can be adjusted for tension by attaching atleast its lower end to a threaded pin (not shown), for example, so thatby rotating the pin tension can be applied to the common actuator wire60.

The detecting device 58 can be any suitable device which provides highsensitivity with a wide dynamic range, such as a strain gauge, whichoutputs an electrical signal proportional to the force applied, orpiezoelectric devices The detecting device 58 is preferably presetwithin a pre-determined operating range so that any change in thetension (plus or minus), due to cutting the wire or spreading it apart,will actuate at least one of the detecting devices 58 and probably thetwo detecting devices 58, on either side of the potential intrusion,

In order to improve the effectiveness of the system 50, the detectorposts 56 are preferably located a distance apart, which ensures that anyvertical motion of the wires (owing to intrusion attempts to force thewires apart) is detected by at least one of the sensors (detectingdevice 58) attached to the detector posts 56. In addition, since thedistance between the detector posts 56 is relatively short, each of thedetecting devices 58, either side of an attempted intrusion or tamperingwith the wires, will be activated.

Thus, the control center 66 to which the detecting devices 58 areconnected, can accurately identify the location of the attemptedintrusion, allowing for a swifter response by the security forces, whichis a further advantage over prior art intrusion detection fences.

The preferred distance between detector posts 56 is relatively shorterthan prior art systems which means that, since the taut wires 52 areattached to the common actuators 60 every 6-8 meters, the fence iseffectively more secure and less liable to natural deflection due to thedistance between common actuators. The detection system 50 of thepresent invention has advantages over the prior art systems since thedetector posts 56 cannot be disabled. The detector posts 56 are securedwithin the ground and each of them equipped with an active transducer 58connected to common actuators 60, so that, in contrast to prior artsystems using wire guiding poles or helical wire supports, the wiresconnected to the detector posts 56 do not have a sliding motion.Instead, the wires are connected to the common actuators 60. Therefore,the detector posts 56 themselves are sensitive to any movement. Inaddition, whenever there is tampering with the wires 52, there is adirect actuation of the detecting devices 58 close to the location ofthe intrusion attempt, in contrast to the indirect actuation of priorart common actuator systems which are generally located further away.

Furthermore, there is a built-in redundancy since generally at least twodetecting devices 58 will be activated at any time (that is, except atthe ends of fence next to the anchor posts 54) and thus if one of thedetecting devices 58 is inoperative, at least one of the others will beactivated. Also, though there are additional detector posts 56 anddetecting devices 58, the extra cost is at least partly offset by thesaving in the cost of intermediate supports (guiding posts or helicalwire supports).

In addition, the extra cost is substantially less than the prior art“sensor per wire” type systems due to the fact that each detector postis itself is effectively a common actuators.

Reference is now made to FIGS. 5 and 6 which illustrate a preferredembodiment of a detector post, generally designated 70. FIG. 5 is anisometric illustration of detector post 70 and FIG. 6 is an enlargeddetail illustrating the connection of the actuator wire 72 to thedetector post 65.

Elements of this embodiment of the invention which are similar toelements which have been previously described with respect to thepreferred embodiment hereinabove, are similarly designated and will notbe further described.

Detector post 70 is anchored to the ground and supported by means of apair of struts 74, suitable attached to the detector post 70. In thispreferred embodiment, each detector post 70 supports a first active (orsensitive) common actuator wire, referenced 72, and a second passive (ornon-sensitive) wire 76 (best seen in FIG. 6).

Common actuator wire 72 and passive wire 76 are parallel to each otherand both the common actuator wire 72 and passive wire 76 are suitablyattached to each end of detecting post 65 by use of upper and lowerrestraining brackets 82. The tension of the common actuator wire 72 andpassive wire 76 are adjustable by means of tensioner bolts 84 fitted tothe lower restraining bracket 82 and attached to both common actuatorwire 72 and passive wire 76.

Common actuator wire 72 is attached to each of the taut trip wires 52 bymeans of a pair of clamping discs 78 suitably fitted together so as totightly grin the trip wire 52 to the common actuator wire 72.

In this embodiment, a detecting device 86 is suitably attached to thedetector post 70. Detecting device 86 consists of a torque sensitivedetector housed within the central leg 90 of a generally “I” shaped(when viewed in plan) housing 88. Housing 88 further comprises a bottomleg 92 which is configured to accept a pair of bolts (not shown) forattaching to the detector post 70 and a top leg 94.

A pair of clamps 96 and 98 are suitably attached to top leg 94 to allowor clamping common actuator wire 72 and passive wire 76, respectively.

An intrusion or an attempt to force the taut wires 52 apart causes thecommon actuator wire 72 to move vertically (indicated by arrow 1000.Since the passive wire 76 is not attached to the taut wires 52, passivewire 76 is not affected. The net movement generated by the commonactuator wire 72 results in the top leg 94 being rotated (indicated byarrow 102) and the consequent torque being detected by the torquesensitive sensor of detected device 86.

An advantage of this embodiment is that the detecting device 86 is notaffected by changes in temperature. Since there are a pair of parallelwires (common actuator wire 72 and passive wire 76) which are clamped tothe detecting device 86, any vertical movement (arrow 100) in theparallel wires owing to temperature changes are equal. Thus, temperaturechanges do not result in any torque movement of top leg 94 and thetorque sensitive sensor of detecting device 86 is not activated.

Reference is now made to FIGS. 7-10. FIG. 7 is a schematic illustrationof a detection system, generally indicated 100, constructed andoperative in accordance with a further embodiment of the presentinvention FIG. 8 is an enlarged detail of the detection system 100.

FIG. 9 is an enlarged detail (reference A In FIG. 8) isometricillustration of the anchor post 108 and FIG. 10 is an enlarged detail(reference B In FIG. 8). illustrating the connection of the actuatorwire 110 to the detector post 108.

Elements of this embodiment of the invention which are similar toelements which have been previously described with respect to thepreferred embodiment hereinabove, are similarly designated and will notbe further described.

Detection system 100 comprises a plurality of fence units, generallyreferenced 102, having a plurality of trip wires 106 which are tautlysecured between a pair of anchor posts 105 at either end (only one isshown in FIG. 8 for clarity). Each fence unit 102 comprises a pair ofguiding posts 104 through which the plurality of trip wires 106 slidethrough. A detector post 108 is located between each pair of guidingposts 104. Anchor posts 105, guiding posts 108 and detector post 108 arepreferably fixed to the ground to prevent movement.

Each detector post 108 has at least one detecting device 122 attachedtherto. The detecting device 122 is connected to at least one commonactuator wire 110. The common actuator wire 110 is attached to each ofthe taut trip wires 106 by any suitable means, such as a clip device 120which is itself suitably connected to the trip wires 106.

In the exemplary embodiment, each common actuator wire 110 travels fromthe top restraining bracket 124 t of one of the pair of guiding posts104, diagonally downwards towards the bottom restraining bracket 124 bof the second of the pair of guiding posts 104. Each common actuatorwire 110 is tensioned between the guiding posts 104. Thus, each guidingpost has a common actuator wire 110 fixed to its top and bottom.

For the purposes of illustration only, detector post 108 is located.approximately mid-way between each guiding post 104.

In an exemplary embodiment, the distance (W) between guiding posts 104is 6 meters. A plurality of the fence units 102 are each coupled to oneof a plurality of field units (or local control center) 114, which aresituated a distance L along the fence line. In this exemplaryembodiment, a local field unit is located along every 100 mn of fenceline. Each of the local field units 114 are suitably connected to acontrol center 116, preferably via a RS 485 communications line 118.

In a further alternative embodiment, a detecting device 123 is suitablycarried by anchor posts 105. A second actuator wire 125 is suitablyfixed and tensioned between the top and bottom of the anchor post 105 bythe use of restraining brackets 124 (or similar).

Alternatively, the common actuator wire 110 attached to the bottom ofone of the anchor posts 105 may be continued vertically throughdetecting device 123 along the anchor post 105 and fixed to the toprestraining bracket. Similarly, the common actuator wire 110 attached tothe top of the second anchor post 105 may be continued vertically downthrough detecting device 123 along the anchor post 105 and fixed to itsbottom restraining bracket.

In another alternative embodiment, the second actuator wire 125comprises two separate wires, one wire fixed to the top restraint 124and the detecting device 123 and the second wire fixed to the bottomrestraint 124 and detecting device 123.

Alternatively, a detecting device is fixed to the anchor posts 105.

Preferably, common actuator wire 110 can be adjusted for tension byattaching at least its lower end to a threaded pin (not shown), forexample, so that by rotating the pin tension can be applied to thecommon actuator wire 110.

The detecting devices 122 and 123 can be any suitable device, (such asthe device 90 described hereinabove with respect to FIG. 6), whichprovides high sensitivity with a wide dynamic range, such as a straingauge, which outputs an electrical signal proportional to the forceapplied. or piezoelectric devices.

The detecting devices 122 is preferably preset within a pre-determinedoperating range so that any change in the tension (plus or minus), dueto cutting the wire or spreading it apart, will actuate at least one ofthe detecting devices 122.

The detecting devices 123 attached to the anchor post 105 senses anystrain applied to the anchor post 105 due to an intruder climbing theanchor post 105.

The detector posts 108 are located a relatively short distance apart, toensure that any vertical motion of the wires (owing to intrusionattempts to force the wires apart) is detected by the detecting devices122) attached to the detector posts 108. Thus, the control center 116(connected to local field units 114 to which the detecting devices 122are connected) can accurately identify the location of the attemptedintrusion.

As described hereinabove with respect to FIGS. 4-6, the detector posts108 are sensitive to any movement. In addition, whenever there istampering with the wires 106, there is a direct actuation of thedetecting devices 122 close to the location of the intrusion attempt.

Detecting devices 122 and 123 are any suitably device such as the torquesensitive sensor detecting device (referenced 86, described hereinabovewith respect to FIG. 6).

It will be appreciated by persons skilled in the art that the presentinvention is not limited to what has been particularly shown anddescribed hereinabove. Rather the scope of the present invention isdefined only by the claims which follow.

What is claimed is:
 1. An intrusion detection fence, comprising: aplurality of trip wires secured between a pair of anchor posts; aplurality of detector posts anchored in the ground, located between saidanchor posts; at least one actuator attached to each of said detectorposts, said at least one actuator also being attached to each of saidplurality of trip wires; a detecting device attached to said at leastone actuator and secured to each of said detector posts; whereindeflection or cutting of any of said plurality of trip wires activatesat least one of said detecting devices adjacent to said activated tripwires.
 2. A fence according to claim 1, wherein deflection of any ofsaid plurality of trip wires activates each of the detecting deviceseither side of the activated trip wires.
 3. A fence according to claim1, wherein said at least one actuator is an actuating wire tensionedbetween the ends of said detector post.
 4. A fence according to claim 1,wherein said at least one actuator is an actuator bar or flange.
 5. Afence according to claim 1 and further comprising: a passive wireattached to each of said detecting device, said passive wire beingparallel to said at least one actuator.
 6. A fence according to claim 5wherein said detecting device is housed within a central leg of agenerally “I” shaped housing, said housing further comprising a bottomleg and a top leg attached to said central leg.
 7. A fence according toclaim 6 wherein said housing further comprises a pair of clamps attachedto said top leg for clamping common actuator wire and passive wire tosaid detecting device.
 8. A fence according to claim 1 wherein saiddetecting device is a torque sensitive device.
 9. A fence according toclaim 1, and further comprising a plurality of guiding posts, eachguiding post being located between each pair of detecting posts orbetween a anchor post and a detecting post.
 10. A fence according toclaim 9, wherein said at least one actuator is an actuating wiretensioned between the top of one of said guiding posts and the bottom ofthe adjacent guiding post.
 11. A fence according to claim 9, whereinsaid at least one actuator is an actuating wire tensioned between oneend of one of said plurality of guiding posts and the end of one of theanchor posts.
 12. A fence according to claim 9 and further comprising asecond detecting device attached to at least one of said pair of anchorposts.
 13. A fence according to claim 12, wherein said actuating wire isfurther tensioned between the top and bottom ends of said at least oneof said pair of anchor posts and attached to said second detectingdevice.
 14. A fence according to claim 12, wherein said actuating wireis further tensioned between the top or bottom end of said at least oneof said pair of anchor posts and attached to said second detectingdevice.
 15. A fence according to claim 20, and further comprising asecond actuating wire attached to and tensioned between the top andbottom ends of said anchor post and attached to said second detectingdevice.
 16. A fence according to claim 12, further comprising second andthird actuating wires, said second actuating wire being tensionedbetween one end of said at least one of said pair of anchor posts andsaid third actuating wire being tensioned between the other end of saidat least one of said pair of anchor posts.
 17. A fence according toclaim 12, wherein said second detecting device is a torque sensitivedevice.
 18. An intrusion detection system, comprising: a fence having: aplurality of trip wires secured between a pair of anchor posts, aplurality of detector posts anchored in the ground, located between saidanchor posts; at least one actuator attached to each of said detectorposts, said actuator also being coupled to each of said plurality oftrip wires; a detecting device attached to said at least one actuatorand secured to each of said detector posts; and a control center coupledto each of said detecting devices, said control center comprising: aprocessor for determining and indicating the location of detectingdevice activated by the deflection of any of said trip wires.
 19. Asystem according to claim 18, wherein defelection of any of said tripwires activates each of the detecting devices either side of theactivated trip wires and wherein said processor determines and indicatesthe location of said intrusion.
 20. A system according to claim 18,wherein said at least one actuator is an actuator bar or flange.
 21. Asystem according to claim 18, wherein said at least one actuator is anactuating wire tensioned between the ends of said detector post.
 22. Asystem according to claim 18 and further comprising: a passive wireattached to each of said detecting device, said passive wire beingparallel to said at least one actuator.
 23. A system according to claim22 wherein detecting device is housed within a central leg of agenerally “I” shaped housing, said housing further comprising a bottomleg and a top leg attached to said central leg.
 24. A system accordingto claim 23 wherein said housing further comprises a pair of clampsattached to said top leg for clamping common actuator wire and passivewire to said detecting device.
 25. A system according to claim 18wherein said detecting device is a torque sensitive device.
 26. A systemaccording to claim 18, and further comprising a plurality of guidingposts, each guiding post being located between each pair of detectingposts or between a anchor post and a detecting post.
 27. A systemaccording to claim 26, wherein said at least one actuator is anactuating wire tensioned between the top of one of said guiding postsand the bottom of the adjacent guiding post.
 28. A system according toclaim 26, wherein said at least one actuator is an actuating wiretensioned between one end of one of said plurality of guiding posts andthe end of one of the anchor posts.
 29. A system according to claim 26,and further comprising a second detecting device attached to at leastone of said pair of anchor posts.
 30. A system according to claim 29,wherein said actuating wire is further tensioned between the top andbottom ends of said at least one of said pair of anchor posts andattached to said second detecting device.
 31. A system according toclaim 29, wherein said actuating wire is further tensioned between thetop or bottom end of said at least one of said pair of anchor posts andattached to said second detecting device.
 32. A system according toclaim 29, and further comprising a second actuating wire attached to andtensioned between the top and bottom ends of said anchor post andattached to said second detecting device.
 33. A system according toclaim 29, further comprising second and third actuating wires, saidsecond actuating wire being tensioned between one end of said at leastone of said pair of anchor posts and said third actuating wire beingtensioned between the other end of said at least one of said pair ofanchor posts.
 34. A system according to claim 29, wherein said seconddetecting device is a torque sensitive device.